Developing Device Contact Member Restriction for Image Integrity

Solution Overview

Problem

The existing developing devices in image forming apparatuses face issues with developer flow and air flow due to pressure differences, leading to potential clogging and disorder of latent images, especially when subjected to external impacts during handling and distribution.

Innovation Solution

A developing device with a deformable contact member and a restriction member is designed, where the contact member extends into the container to block air flow through the gap and the restriction member maintains the contact member's posture to ensure developer return, preventing clogging and maintaining image integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a contact member is provided to block air flow through the gap between the developer holding body and container, then air flow and developer disorder are prevented, but the contact member may deform toward the outer side under external impact, causing developer leakage

Engineering Contradiction:

Improveprevention of developer leakageVSAvoidresistance to external impact

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The contact member is designed as a deformable member that can elastically deform under external impact forces. This flexibility allows the contact member to temporarily move toward the outer side of the container during impact, absorbing the shock energy, while still maintaining its blocking function to prevent developer leakage under normal operating conditions.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The deformable contact member acts as a cushioning element that anticipates and absorbs external impact forces before they can cause developer leakage. By being positioned to contact the developer holding body and be capable of deformation, it provides pre-positioned protection against impact-induced leakage.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Reliability

If the contact member is made rigid to maintain blocking function, then air flow is effectively blocked, but the device becomes vulnerable to deformation and malfunction under external impact

Engineering Contradiction:

Improveblocking function maintenanceVSAvoidsensitivity to external impact

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The contact member is designed as a deformable member that can elastically deform under external impact forces. This flexibility allows the contact member to temporarily move toward the outer side of the container during impact, absorbing the shock energy, while still maintaining its blocking function to prevent developer leakage under normal operating conditions.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The contact member's physical state is changed from rigid to deformable, allowing it to dynamically adjust its position and shape in response to external forces. This parameter change enables the member to maintain blocking function during normal operation while accommodating impact forces without permanent deformation or malfunction.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If no restriction member is provided, then the structure remains simple, but the contact member deforms under external impact causing developer flow disorder and clogging

Engineering Contradiction:

Improvestructural simplicityVSAvoidprevention of developer flow disorder

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The restriction member serves as an intermediary element between the contact member and the developer holding body. It provides a controlled interface that guides the contact member's deformation, ensuring that even when the contact member moves under external impact, it does so in a manner that prevents developer flow disorder and clogging while maintaining the overall simplicity of the structure.

Inventive Principle:

Principle #24Intermediary (Mediator)

4Reliability

If the contact member extends far into the container to effectively block air flow, then air leakage is prevented, but the contact member becomes more susceptible to deformation under external impact

Engineering Contradiction:

Improveair flow blocking effectivenessVSAvoidcontact member posture stability

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The contact member is designed as a deformable member that can elastically deform under external impact forces. This flexibility allows the contact member to temporarily move toward the outer side of the container during impact, absorbing the shock energy, while still maintaining its blocking function to prevent developer leakage under normal operating conditions.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The deformable contact member acts as a cushioning element that anticipates and absorbs external impact forces before they can cause developer leakage. By being positioned to contact the developer holding body and be capable of deformation, it provides pre-positioned protection against impact-induced leakage.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution effectively prevents developer flow through the gap during pressure differences, ensuring reliable developer return to the container and maintaining image quality by restricting the contact member's posture, thus addressing clogging and image disorder issues.

Implementation Method 1

pressure differences, leading to potential clogging and disorder of latent images

Methodology Applied

Scientific EffectPressure difference: Pressure Gradient

Implementation Method 2

the restriction member is disposed on an image holding body side of the contact member and restricts the tip end of the contact member from deforming so as to be in a state where the contact member is directed toward an outer side of the container

Methodology Applied

Scientific EffectMechanical constraint: Mechanical Force

Implementation Method 3

a developer holding body which supplies a developer to an image holding body on which an electrostatic latent image is formed

Methodology Applied

Scientific EffectElectrostatic attraction: Electrostatics

Data Source

PatentUS9588458B2Developing device and image forming apparatus

Publication Date: 2017.03.07 FUJIFILM BUSINESS INNOVATION CORP

AI summary

A developing device includes a developer holding body, a container, a contact member, and a restriction member. The developer holding body supplies a developer to an image holding body. The container accommodates the developer holding body and is formed with an opening portion facing the image holding body. The deformable contact member is fixed in the container and on a downstream side of the opening portion body in a rotation direction of the developer holding body and includes a tip end which extends toward an inner side of the container and which contacts with the developer holding body. The restriction member is disposed on an image holding body side of the contact member and restricts the tip end of the contact member from deforming so as to be in a state where the contact member is directed toward an outer side of the container.